I couldn't install speex until I installed automake-1.8. It failed during aclocal because /usr/bin/aclocal-1.8 was missing.
Some more information, like the exact output (or logfile) of what failed, and emerge --info output, are appreciated :)
Works for me. Tested in stable amd64 chroot with only automake 1.7.9-r2 installed before. As the ebuild inherits 'autotools' the latest automake (1.11.1 atm) gets automatically pulled in and installed as DEPEND.
emerge --info and build.log missing...